It will be fine. I don't think it makes much difference having them back there you just probably want to raise the outers to where there's not much effect and use the inners to stabilize the hull at upper speeds. When CG/prop is right these boats can run with everything pretty much flat.
One trick on the exhaust if using a SS header is to heat it cherry and give it a little tweak adding bend and it gets the pipe right between the radio box and the edge of the opening. Makes it so you have more material left on canopy on the left side as sometimes it is into the deck even without a little tweak.
Building another Assault here soon.